The concern for customers is: (a) making their credit card details available to the web site, and
(b) never seeing the products they have ordered.
To help allay your fears, there are some factors that you can take into account. If the web page offers a telephone number, then that in itself is a way of saying that that supplier is reputable.
The next thing to look for is the layout of a website and the access from one page to others, particularly product pages. There is a great deal of cost in setting up a web page, which is beyond the means of a shonky operator. So if a web site offers flexability then it will be OK.
Finally, there is TLS/SSL security in the form of Cryptographic Protocols that prevents eavesdropping and tampering so that your credit card details or PayPal details remain confidential. The credit card details are not even available to the webpage operator, which in fact makes it more secure than giving your credit card details on the 'phone.
But if you still have a concern, then for peace of mind.....'phone.
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